This invention relates to a printer head used in a printer for printing on cards. More particularly, the invention relates to a printer head used in a printer for printing on the surface of cards made of plastic or paper by means of an electrical system.
Many printer heads have been developed for use in electrical printers capable of printing on the surface of cards made of plastic or paper. One example of such printer head is of a structure in which an electric current is made to flow instantaneously in accordance with a print signal from an electrode pin connected to a positive electrode of a signal source toward an ink ribbon connected to a negative electrode, the ink on the ink ribbon is fused by Joule heat generated directly below the energized electrode pin, and the fused ink is transferred to the plastic or paper card as a dot, which constitutes the minimum printing unit. In the conventional printer head of this type, the electrode pin is mounted on a single frame, which is driven by a solenoid, either directly or via simple cushion mechanism. This results in a problem wherein the electrode pin is pressed against the card surface too lightly, too strongly or unevenly. In addition, to pass the electric current into the ink ribbon, it is required that the ink ribbon side be connected to the negative electrode in a reliable manner. In the conventional printer head, however, the state of the connection is imperfect, as a result of which the current cannot be passed through the ribbon reliably.